Quartz heaters with Metal Elements. Each single tube quartz heater consists of heating elements+Quartz tube+single guard Quartz heaters with Metal Elements.0.5 to 30 kW, 26 watts/square inch (4 watts/square centimeter) nominal. 120, 240, 480 volts standard, 208, 380, 415 and other voltages available. For plating tanks, pickling and other acidic aqueous solutions. Not for use in hydrofluoric acid ...